Hobie Forums
http://www.hobie.com/forums/

spacing for TI cradles
http://www.hobie.com/forums/viewtopic.php?f=71&t=45416
Page 1 of 2

Author:  Tom Kirkman [ Mon Oct 22, 2012 4:13 pm ]
Post subject:  spacing for TI cradles

Can someone point me to the recommended spacing for the Hobie TI cradle set? Trying to get this in motion before the boat actually arrives. Thanks in advance.

Author:  Herbaldew [ Mon Oct 22, 2012 4:33 pm ]
Post subject:  Re: spacing for TI cradles

Jbernier wrote:
All of our cradles use the same 67" spacing (because we designed them all to work on the same trailer)

Author:  Tom Kirkman [ Mon Oct 22, 2012 5:31 pm ]
Post subject:  Re: spacing for TI cradles

Outstanding. Thanks.

Author:  FraznDaf [ Wed Oct 24, 2012 9:17 am ]
Post subject:  Re: spacing for TI cradles

Easier Said than Done!
I laid on the ground under my trailer looking at Cradle fit on the Hull
My impression was the cradles hugged the hull better away from the Mirage drive wells, so the 67" spacing ie Mirage well spacing, was off.

If I shoved the cradles right under the Mirage drive well, it pinched the Hull chines together or you had one cradle ridge impacting the hull at a weird point/angle.

I'm now looking at sticking with 2 - 6" carpet bunks alongside each other placed under the Mirage wells to spread the weight out and reduce hull deformation after sitting a long time on the trailer bunks

Author:  maurizio [ Wed Oct 24, 2012 10:09 am ]
Post subject:  Re: spacing for TI cradles

my personal and recent experience with the cradles for the TANDEM tells me:
put the tandem on the trailer and you'll find the right spaces, otherwise you'll get surprises with matching white ( empty spaces) with the hull

Author:  tonystott [ Wed Oct 24, 2012 10:43 am ]
Post subject:  Re: spacing for TI cradles

I have never seen it said that the cradles are supposed to align with the Miragedrive wells. This sounds to be spurious to me considering that Hobie use the same 67 inch spacing for the AI, PA and TI, only one of which even has two Miragedrives.

My trailer guy got under the trailer and slid the cradles until they fitted well, and neither aligns with a Miragedrive

Author:  Tom Kirkman [ Wed Oct 24, 2012 11:51 am ]
Post subject:  Re: spacing for TI cradles

I set the initial spacing on my AI at 67 inches, then slid the boat around until it seemed to fit best, then adjusted the cradles a bit to get things even better. They ended up at 66 inches apart and the forward cradle sits just behind the forward Ama crossbar.

Knowing that the TI is designed to fit with the same spacing, I have a good starting place to work from. That's what I was after. No doubt I'll adjust as needed, but this will get me close out of the gate. Thanks.

The boat arrived today. Got it unpacked. Hope we have good wind this weekend.

Author:  tonystott [ Wed Oct 24, 2012 4:13 pm ]
Post subject:  Re: spacing for TI cradles

Are you sure about placement so the front cradle sits just behind the forward crossbar? On my TI, the front cradle sits behind the front drivewell. The distance of the crossbar from the bow is 4" shorter on a TI compared with an AI, so that doesn't explain the big difference. If I had my TI front cradle where you suggest, I would only have the really skinny part of the amas on them.
Image

Author:  Tom Kirkman [ Wed Oct 24, 2012 4:22 pm ]
Post subject:  Re: spacing for TI cradles

You mis-read - I said that it said just behind the front crossbar on my AI, not TI.

I have to play around with the TI a bit to see where it will fit best.

Author:  tonystott [ Wed Oct 24, 2012 4:57 pm ]
Post subject:  Re: spacing for TI cradles

Tom, I didn't misread your comment at all, as I said that the crossbar on an AI is only 4 inches further back than the TI one. Yet my front cradle doesn't sit "just behind the crossbar" plus 4 inches, but sits considerably further back (the whole length of the drivewell actually). Distance from the bow to the bolt line of the front cradle is approximately 82 inches on my TI. (This is why I have a roller to support the hull about halfway to the bow, and another doing the same job halfway from the rear cradle to the stern)

Spacing between the cradles turned out to be 67 inches, which was arrived at by the trailer guy lying underneath and sliding the cradles to where the best fit was. He was not even aware of the "magic number" of 67.

Hope this clears up any misunderstanding, and gives you a a starting point for your TI trailer setup.

Author:  Tom Kirkman [ Wed Oct 24, 2012 5:02 pm ]
Post subject:  Re: spacing for TI cradles

Sorry, wasn't sure you noted the AI comment.

The front support on my AI trailer does indeed fall exactly in line with the rear of the Ama crossbar. And the boat fits perfectly on the cradle at that point.

I supposed this goes back to the fact that one of these boats are identical in shape.

Author:  Tom Kirkman [ Fri Oct 26, 2012 11:57 am ]
Post subject:  Re: spacing for TI cradles

I turned the boat over and slid the cradles back and forth to find the best possible fit. With the "points" of the cradles sitting in the dual troughs on the bottom of the hull, the spacing between cradle centerlines is a scant 54 inches. But anything more than an inch closer or further results in a horrible fit.

Image

I'm still going to have to raise the center of the cradles so that the mid hull area will actually sit on the cradle (only the outer 1/3rd hulls touch), but this is as good as it gets with this boat and these cradles. As I suspected, when dealing with plastic boats it may be a little too much expect an absolute perfect fit, on every boat, with the same spacing.

Author:  tonystott [ Fri Oct 26, 2012 12:44 pm ]
Post subject:  Re: spacing for TI cradles

Tom,
I would suggest that you don't mount the cradles at 54 inch spacings, but wait until you have the amas fitted, and swung back in the akas, as then you will need to come up with a compromise to best fit all three hulls.

I can agree that differences between individual Islands make choosing a single measurement of say 67 inches potentially incorrect, which is why in my opinion, sliding the cradles back and forth under the Island while on the trailer is going to provide the best real-world solution. The measurement is then irrelevant.

Author:  Tom Kirkman [ Fri Oct 26, 2012 1:15 pm ]
Post subject:  Re: spacing for TI cradles

I would like the bulk of the weight to be on the hull, not the Amas and Akas. So the 54 inches is the only spacing that puts the main hull itself on the cradles. Not to mention, that the upward "V" of the cradles only matches that of the hull with the 54 inch spacing. It is what it is, I'm afraid. This is the only place they'll come anywhere close to fitting.

Author:  Puget [ Sun Oct 28, 2012 2:33 pm ]
Post subject:  Re: spacing for TI cradles

Tom,

You’re question about cradle spacing made me rethink my TI trailer again. I’d guess that spacing is less important for driving a few hours than for long term storage. Someone on the forum said that pressure over time will cause the plastic in the hull to flow away from the pressure point. So my concern is supporting all of the weight evenly. With 2 cradles the problem is not so much where the cradles are, but whether the bow and stern are supported.

Tony said he uses rollers between the bow and forward cradle, and between the stern and aft cradle. I put a roller (on the winch) 7 inches from the bow, which leaves 82 inches unsupported before the forward cradle. However, this is a narrow lightweight part of the boat. My problem is putting a support near the heavier stern, since the TI is 5 or 6 feet longer than a Trail-X trailer useable tongue length.

With the TI stern hanging 5 feet (plus the rudder) off the end of the aft cradle for 8 months, I have not noticed any deformation of the hull. But then we’ve had a cool summer here around Seattle, and I’ve taken the boat out a fair amount. When sailing gets less frequent over the winter I plan to block up the stern. I wish the tongue were somewhat longer so I could mount a roller further back. But then launching and retrieving might be more difficult.

Good luck with you’re trailer. Must be some big surf around there now.

Puget

Page 1 of 2 All times are UTC - 8 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/